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You can put this solution on YOUR website!
In equations, there are 2 \"sides\" on either side of the = sign. In your problem, there are 3 \"sides\", so we add, subtract, multiply, divide all 3 sides:
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\n" ); document.write( "-45 < -5x - 15 < 45
\n" ); document.write( "-30 < -5x < 60 (added 15 to all 3 \"sides\")
\n" ); document.write( "Now, we have to divide by a negative, so we need to make all the < turn to >. If you want to know why this is, look below.
\n" ); document.write( "-30 < -5x < 60
\n" ); document.write( "6 > x > -12 (divided all 3 \"sides\" by -5)
\n" ); document.write( "-12 < x < 6 (flipped the whole thing around because it's nice to read from the smallest number)
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\n" ); document.write( "So why do we flip the < sign? Here's an example:
\n" ); document.write( "5 < 10 (true)
\n" ); document.write( "Let's arbitrarily divide both sides by -1:
\n" ); document.write( "-5 < -10 (no longer true!)
\n" ); document.write( "So, when we divide by negatives, we must flip the inequality signs:
\n" ); document.write( "-5 > -10\r
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